llvm jit

hello,
I have a question about the llvm jit.
Does it use the profile information generated during runtime to enhance the generated code for arm processor?
according to 'LLVM: A Compilation Framework for Lifelong Program Analysis ’ it is available but can’t find it in the current source code.
I really appreciate any help.

Thanks in advance
Sara,

No, the JIT does not do any profile guided optimizations for any architecture. It just uses the static compilation components before loading the object into memory and running its own dynamic linker.

Amara

So, what is the use of the profile passes in LLVM?
Also, does llvm detect hot blocks of code for recompilation?

So, what is the use of the profile passes in LLVM?

Mainly basic block placement.
More is coming.

Also, does llvm detect hot blocks of code for recompilation?

No.
LLVM is a low level virtual machine. It provides the infrastructure and
capabilities necessary to do the actual recompilation/etc. What is there
is not intended to be a full, high level virtual machine on it's own.